This image is part of a series that was created for an open textbook, Cell Biology, Genetics and Biochemistry for PreClinical Students. The textbook will be available Late 2021.
Preferred citation:
Kindred Grey (2021). "Metabolism of methionine." CC BY 4.0.
Alternative text:
Circular diagram homocysteine arrow enzyme homocysteine methyltransferase with N5-menthyl-THF arrow THF to methionine arrow enzyme methionine adenosyltransferase with ATP arrow 3 Pi to S-adenosylmethionine (SAM) arrow enzyme methyltransferases with loss of CH3 (used for methylation) to S-adenosylhomocysteine (SAH) arrow enzyme S-adenosylhomocysteine hydrolase to adenosine dotted arrow to nucleotide salvage. Homocysteine arrow enzyme cystathionine β-synthase with serine addition to cystathionine arrow enzyme cystathionine ᵞ-lyase with loss of α-ketobutyrate to cysteine arrow enzyme cysteine dioxygenase with O2 addition to cysteine sulfinate arrow enzyme cysteine sulfinate decarboxylase with loss of CO2 to hypotaurine arrow enzyme hypotaurine dehydrogenase with NAD+ arrow NADH to taurine arrow bile salts. Cysteine sulfinate bidirectional arrow enzyme transaminase with α-ketoglutarate bidirectional arrow glutamate to β-sulfinylpyruvate arrow with loss of sulfite to pyruvate. Sulfite arrow enzyme sulfite oxidase to sulfate. Threonine arrow enzyme threonine dehydratase with loss of NH4+ and H2O to α-ketobutyrate dotted arrow text (in mitochondrial matrix) to succinyl-CoA dotted arrow TCA. Cysteine dotted arrow glutathione, coenzyme A